@media screen and (max-width: 748px) {
    header{
        width: 100%;
    }
    .header_img{
        width: 100%;
        height: 100%;
    }
    .main_top {
        display: none;
    }

    #pc{
        display:none
    }
 
    
}

@media screen and (min-width:749) {
        #h5{
            display: none;
        }
}